\ Paper reference: HESS Collaboration, 2020 - On GRB 190829A
\ XRT butterfly for the observation of the GRB 190829A during the HESS first night of observation
\ Extracted from original analysis done by Phil Evans (U. Leicester)
\ tstart = 15633 s
\ tstop = 27746 s
|            energy|                  flux|         flux_error_hi|         flux_error_lo|
|            double|                double|                double|                double|
|                eV|       1 / (cm2 keV s)|       1 / (cm2 keV s)|       1 / (cm2 keV s)|
|              null|                  null|                  null|                  null|
 299.99999999999994      0.196372729677754   0.022808281918755918    0.02008217327815978 
 360.80518302810395    0.13497999536711155    0.01402099720532013   0.012474980877559327 
  433.9346003331454    0.09278069912866041    0.00851135909233268   0.007651473368726583 
  521.8861763180922     0.0637743252797625   0.005084820431347267   0.004617684968489064 
  627.6641245542887    0.04383632159581979  0.0029746725861617834  0.0027281350514470407 
   754.881564466616   0.030131609901358294  0.0016908757492583686  0.0015653662459540058 
  907.8839367730628   0.020711453018772714  0.0009217254829882969  0.0008606557645787945 
 1091.8974332522685   0.014236354697048299  0.0006247286972351392  0.0005855306683709254 
 1313.2075108416723   0.009785590362803959  0.0005414360742816305  0.0005056517637026213 
 1579.3735876770345   0.006726284978587653 0.00045000709937002663 0.00041770901114586943 
 1899.4872545718856   0.004623421575579829 0.00036341256316299846 0.00033480152578359117 
 2284.4828218178664  0.0031779841522601533 0.00028738688576040875  0.0002625461791841751 
  2747.510808835182  0.0021844391879297918 0.00022366104100204464 0.00020250129738217694 
  3304.387134178239  0.0015015098682508304    0.00017188863625504  0.0001541727483175422 
 3974.1333491429737   0.001032087272977033  0.0001307640573949575 0.00011615679735120607 
  4779.626368052075  0.0007094220035210752  9.864804847601368e-05  8.676519122921675e-05 
 5748.3798884366015  0.0004876327731744601  7.389834596326647e-05  6.434572660189762e-05 
  6913.484192541466   0.000335182331945742   5.50278942354946e-05 4.7428435643489294e-05 
   8314.73643150609 0.00023039303719725823 4.0765613547200384e-05   3.47756529479788e-05 
 10000.000000000002 0.00015836440805468737 3.0064825574379424e-05  2.538215651173709e-05 
